Transient control for switched-capacitor regulators

1. An apparatus, comprising: a switched-capacitor circuit including a plurality of interleave circuits, wherein the switched-capacitor circuit is configured sequentially activate each of the plurality of interleave circuits to generate a particular voltage level on a regulated power supply node, wherein a particular interleave circuit includes a plurality of switches coupled to a plurality of capacitors; and a control circuit configured to: monitor one or more operating parameters associated with the switched-capacitor circuit; detect a regulation event using results from monitoring the one or more operating parameters; and in response to a detection of a regulation event, progressively change a corresponding conversion ratio for each of the plurality of interleave circuits.

2. The apparatus of claim 1 , wherein to activate a given interleave circuit of the plurality of interleave circuits, the switched-capacitor circuit is further configured to: close a first subset of the plurality of switches for a first time period to charge the regulated power supply node using a subset of the plurality of capacitors; and close a second subset of the plurality of switches for a second time period to discharge the regulated power supply node using the subset of the plurality of capacitors; and wherein the first and second subsets of the plurality of switches and the subset of the plurality of capacitors are specified by a particular conversion ratio corresponding to the given interleave circuit.

3. The apparatus of claim 2 , wherein to progressively change the corresponding conversion ratio for each of the plurality of interleave circuits, the control circuit is further configured to: check a switching frequency of a particular interleave circuit of the plurality of interleave circuits; in response to a determination that the switching frequency is less than a threshold value: increase a value of the switching frequency associated with a plurality of switch control signals coupled to the particular interleave circuit; and otherwise, change the corresponding conversion ratio for the particular interleave circuit.

4. The apparatus of claim 3 , wherein to change the corresponding conversion ratio for the particular interleave circuit, the control circuit is further configured to generate the plurality of switch control signals using transition information based, at least in part, on the corresponding conversion ratio.

5. The apparatus of claim 1 , wherein to monitor the one or more operating parameters, the control circuit is further configured to monitor a voltage level of an input power supply node coupled to the switched-capacitor circuit.

6. The apparatus of claim 1 , wherein to monitor the one or more operating parameters, the control circuit is further configured to monitor an output current of the switched-capacitor circuit.

7. A method, comprising: sequentially activating, by a power converter circuit, a plurality of interleave circuits included in a switched-capacitor circuit coupled to a regulated power supply node, wherein a given one of the plurality of interleave circuits includes a plurality of switches coupled to a plurality of capacitors; monitoring one or more operating parameters of the power converter circuit; detecting, by the power converter circuit, a regulation event using results from monitoring of the one or more operating parameters; and in response to detecting the regulation event, progressively changing a corresponding conversion ratio for each of the plurality of interleave circuits.

8. The method of claim 7 , wherein sequentially activating the plurality of interleave circuits includes: closing a first subset of the plurality of switches for a first time period to charge the regulated power supply node using a subset of the plurality of capacitors; and closing a second subset of the plurality of switches for a second time period to discharge the regulated power supply node using the subset of the plurality of capacitors; and wherein the first and second subsets of the plurality of switches and the subset of the plurality of capacitors are specified by a particular conversion ratio corresponding to the given one of the plurality of interleave circuits.

9. The method of claim 7 , wherein progressively changing the corresponding conversion ratio for each of the plurality of interleave circuits includes: checking a switching frequency of a particular interleave circuit; in response to determining that the switching frequency is less than a threshold value: increasing a value of the switching frequency associated with a plurality of switch control signals coupled to the particular interleave circuit; and otherwise, changing the corresponding conversion ratio for the particular interleave circuit.

10. The method of claim 7 , wherein changing the corresponding conversion ratio for a particular interleave circuit includes retrieving transition information from a lookup table.

11. The method of claim 10 , further comprising, determining a next switch control signal of a plurality of switch control signals to assert based on, at least in part, the transition information and independent of a currently asserted switch control signal of the plurality of switch control signals.

12. The method of claim 7 , wherein the one or more operating parameters includes an output current of the power converter circuit.

13. The method of claim 7 , wherein the one or more operating parameters includes a voltage level of an input power supply node coupled to the power converter circuit.

14. An apparatus, comprising: a switched-capacitor circuit coupled to a regulated power supply node, wherein the switched-capacitor circuit includes a plurality of capacitors arranged in a plurality of segments each including at least one capacitor of the plurality of capacitors, and wherein the switched-capacitor circuit is configured, for a given one of a plurality of switching events, to: charge, for a charge period, the regulated power supply node using a given one of the plurality of segments; and discharge, for a discharge period, the regulated power supply node using the given one of the plurality of segments; and a control circuit configured, in response to a determination that a load current being drawn from the regulated power supply node has reached a steady-state, increase a number of segments in the plurality of segments.

15. The apparatus of claim 14 , wherein the switched-capacitor circuit is further configured, for a different one of the plurality of switching events, to: charge, for the charge period, the regulated power supply node using a different one of the plurality of segments; and discharge, for the discharge period, the regulated power supply node using the different one of the plurality of segments.

16. The apparatus of claim 14 , wherein the control circuit is further configured, in response to a detection of a change in load current, to decrease the number of segments in the plurality of segments.

17. The apparatus of claim 16 , wherein the control circuit is further configured to change a conversion ratio associated with the switched-capacitor circuit, in response to the detection of the change in load current.

18. The apparatus of claim 14 , wherein each segment of the plurality of segments includes a respective plurality of switches, and wherein to charge, for the charge period, the regulated power supply node using the given one of a plurality of segments, the switched-capacitor circuit is further configured close, using a plurality of switch control signals, a first subset of a corresponding plurality of switches included in the given one of the plurality of segments.

19. The apparatus of claim 18 , wherein to discharge, for the discharge period, the regulated power supply node using the given one of the plurality of segments, the switched-capacitor circuit is further configured to: open the first subset of the corresponding plurality of switches using the plurality of switch control signals; and close a second subset of the corresponding plurality of switches using the plurality of switch control signals.

20. The apparatus of claim 19 , wherein the control circuit is further configured to generate the plurality of switch control signals using a reference clock signal.